<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
        .up {
            position: relative;
            width: 800px;
            height: 200px;
            background-color: aquamarine;
        }
        .down {
            width: 800px;
            height: 200px;
            background-color: pink;
        }
        .son {
            position: absolute;
            width: 50px;
            height: 50px;
            line-height: 50px;
            text-align: center;
            background-color: rgba(0, 0, 0, 0.3);
            color: white;
            top: 75px;
            left: 750px;
        }
        .daughter {
            position: absolute;
            width: 50px;
            height: 50px;
            line-height: 50px;
            text-align: center;
            background-color: rgba(0, 0, 0, 0.3);
            color: white;
            top: 75px;
        }
    </style>
</head>
<body>
    <div class="up">
        <div class="son">
            >
        </div>
        <div class="daughter">
            &lt;
        </div>
    </div>
    <div class="down">

    </div>
</body>
</html>